[Durgical](https://durgical.com/en/) › [DurgiPedia](https://durgical.com/en/durgipedia/) › [Microbiology](https://durgical.com/en/microbiology/) › [RNA arboviruses](https://durgical.com/en/microbiology/groups/rna-arboviruses/) › Oropouche virus

[Microbiology](https://durgical.com/en/microbiology/) · [RNA arboviruses](https://durgical.com/en/microbiology/groups/rna-arboviruses/)

# Oropouche virus

- Virus
- Enveloped
- For completeness

A virus spread mainly by a tiny biting midge. It causes a dengue-like fever that often comes back days or weeks later.

Updated 2026-11-01

Also called: OROV

## Key points

- Orthobunyavirus with three-segment negative-sense RNA
- Main vector: the midge Culicoides paraensis
- Dengue-like illness with frequent relapses
- Re-emerging in the Americas since late 2023, with cases outside the Amazon

## At a glance

**Shape**
Spherical

**Genome**
Single-stranded, negative-sense RNA in three segments

**Envelope**
Enveloped

**Family**
Peribunyaviridae, genus Orthobunyavirus

**Size**
About 80 to 120 nm

## Morphology

- Enveloped virus with glycoproteins Gn and Gc
- Three RNA segments (large, medium, small) that allow reassortment

## Transmission

- Bite of the midge Culicoides paraensis (main)
- Some Culex and other mosquitoes as possible vectors
- Possible vertical transmission reported in Brazil in 2024

**Reservoir:** Sloths, non-human primates and perhaps birds in the sylvatic cycle; Humans in the urban cycle

**Vector:** Culicoides paraensis (biting midge)

### Isolation precautions

What the care team adds to standard precautions.

- Standard

## Virulence factors

- The segmented genome eases reassortment and the rise of new lineages
- Can invade the central nervous system after the febrile phase

## Diseases it causes

- Oropouche fever, with frequent relapses and, rarely, meningitis or encephalitis [Oropouche fever and other emerging arboviruses →](https://durgical.com/en/conditions/oropouche-fever-and-other-emerging-arboviruses/)

## Clinical picture

- Incubation 3 to 10 days; sudden fever, severe headache, chills, myalgia and arthralgia
- Photophobia, dizziness, nausea, vomiting and rash
- Symptoms recur days or weeks later in a large share of patients
- Rarely aseptic meningitis or encephalitis
- In pregnancy, links with fetal death and microcephaly are under study

## Diagnosis

- RT-PCR on serum in the first week
- IgM toward the end of the first week; neutralization at reference labs
- In neurological disease, CSF serology is more useful than PCR
- Easily mistaken for dengue or chikungunya

## Treatment

There is no specific antiviral: rest, fluids and analgesic-antipyretics such as paracetamol, avoiding NSAIDs until dengue is ruled out.

Drug class only; doses and regimens are set by the clinician from the current guideline.

## Prevention

- Bite protection: covering clothes, fine mesh screens and repellents
- Environmental control of organic waste where midges breed
- No vaccine

## In Colombia

Colombia is among the countries of the Americas with local Oropouche transmission in the regional re-emergence of 2024 and 2025; PAHO rated the regional risk as high.

## Memory aid

Oropouche "rings twice": the fever returns just when the patient thought it was over.

## Test yourself

Think of the answer, then tap the question to see it.

## What is the main vector of Oropouche virus?

The biting midge Culicoides paraensis, a tiny insect distinct from Aedes mosquitoes.

## Which clinical feature points to Oropouche rather than dengue?

Symptoms returning days or weeks after the first febrile episode.

## What kind of genome does Oropouche virus have?

Single-stranded, negative-sense RNA divided into three segments.

[Add to my cards (3)](https://durgical.app/estudiar/?add=/en/microbiology/oropouche-virus/)

## Related

- [Dengue virus](https://durgical.com/en/microbiology/dengue-virus/)
- [Chikungunya virus](https://durgical.com/en/microbiology/chikungunya-virus/)

## Related conditions

- [Oropouche fever and other emerging arboviruses](https://durgical.com/en/conditions/oropouche-fever-and-other-emerging-arboviruses/)

## What the colours mean

**Gram-positive**
Thick peptidoglycan wall: stains purple.

**Gram-negative**
Thin wall with an outer membrane: stains pink.

**Acid-fast**
Lipid-rich wall (mycobacteria): Ziehl–Neelsen stain.

[← Back to the group: RNA arboviruses](https://durgical.com/en/microbiology/groups/rna-arboviruses/)

Educational content on microorganisms; not a treatment guide and no substitute for a health professional's advice. No doses are given.

Sources: [Oropouche virus disease](https://www.who.int/news-room/fact-sheets/detail/oropouche-virus-disease) (World Health Organization (WHO), 2024); [Clinical Overview of Oropouche Virus Disease](https://www.cdc.gov/oropouche/hcp/clinical-overview/index.html) (CDC, 2025).

## **Spotted a mistake?** We are always improving for the community. Tell us what is wrong and our team will review it. Report a mistake

Representative model, for educational purposes only.

---
Source: https://durgical.com/en/microbiology/oropouche-virus/
License: CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Cite as: DurgiPedia (durgical.com), https://durgical.com/en/microbiology/oropouche-virus/